This invention relates to the field of chemical analysis, and in particular to a plasma ion source mass spectrometer.
In the environmental measurement and semiconductor fields, plasma ion source mass spectrometry is being put to practical use as a high sensitivity elemental analysis tool, and its use is rapidly becoming more widespread. As a plasma ion source, an inductively coupled plasma (referred to hereafter as ICP) or a microwave induced plasma (referred to hereafter as MIP) is used, and these sources are combined with a mass spectrometer in commercial devices to measure extremely small quantities of samples.
Japanese Unexamined Patent Publication No. H7-78590 discloses a plasma ion source mass spectrometer comprising a plasma ion source which analyses a sample in a plasma, a sampling interface for leading the generated ions into a vacuum container, an ion optical system disposed in the vacuum container, a mass analyzer and a detector. The axis of the sampling interface and axis of the mass analyzer are disposed at an angle of 90 degrees. The ion optical system comprises a quadrupole type deflector which deflects ions that have passed through the sampling interface by 90 degrees, and the deflector opens onto the opposite side of the sampling interface.
Recently, a quadrupole ion trap mass spectrometer, described simply hereafter as an ion trap mass spectrometer, has been proposed instead of the quadrupole mass spectrometer. The ion trap mass spectrometer is able to accumulate the ions to be measured, which have been led in from outside the mass analyzer into the interior of the mass analyzer surrounding the electrodes, by controlling a high frequency electric field. The accumulated ions are extracted and detected according to m/z (mass/charge ratio).
For this reason, the ion trap mass spectrometer is expected to provide high sensitivity in acquiring mass spectra compared to an ion transmitting type mass spectrometer such as the quadrupole mass spectrometer which transmits ions having a specific m/z in the ions which are introduced. The ion trap mass spectrometer offers the following advantages compared to a transmitting type mass spectrometer such as the conventional quadrupole mass analyzer:
(1) measured ions are retained for a long period inside the apparatus,
(2) measured ions are accumulated in large numbers inside the apparatus,
(3) a series of measurement operations can be completed in a short time, so mass spectra can be integrated a large number of times within a predetermined time and measurement precision is improved,
(4) molecular ions can be dissociated by collisions inside the interior of the mass spectrometer.
Hence, the ion trap mass spectrometer is expected to have new applications in the environmental measurement and semiconductor fields, and as the control portion has been improved, it can now perform more complex control.
This invention therefore aims to provide a device which incorporates a sample in a shorter distance, shortens introduction time and prevents contamination when a sample is introduced by making better use of the high sensitivity characteristics of an ion trap type mass spectrometer.
This invention further aims to provide a compact device which is easy to use.
This invention is characterized in that an ion generating means used for analysis, ion deflecting means and ion analyzing means are disposed on a plane in a horizontal direction, and a means for supplying a sample to the ion generating means is disposed on a plane in the vertical direction, these means being arranged in a two-tier structure wherein the first is disposed on an upper level and the second is disposed on a lower level.
For convenience of design, although these means are disposed in planes, is not necessary that they be disposed in one plane, it being sufficient that they are disposed in planes in proximity to each other. In practice, the device can be made more compact by adopting a two-tier, two plane construction.
In a burner which generates a plasma, containers housing a torch and a nebulizer can be freely attached or detached, and a pump is provided in its lower part for sample induction that allows a sample to be supplied from outside the control portion and enhances ease of use. By making the burner independent, safety is improved compared to the conventional case. According to this invention, safety is still further enhanced by adopting a three cover structure comprising an outer cover to prevent plasma from affecting the outside environment, a maintenance cover and a burner cover.
Another feature of this invention is that, apart from the fact that the burner is an independent container, an ion deflecting portion and ion analyzing portion form a block inside one container, and the ion introducing portion between the burner and deflecting portion also forms a block in one container, these being arranged inside a basis to form a two-tier/two plane construction.
Further, by arranging plural matching boxes (construction units housing electrical circuits) inside the excess space, the block construction is developed further.
This invention specifically provides the following devices.
This invention provides a plasma ion source mass spectrometer wherein a sample is converted to ions in a plasma, the ions are deflected to give a mass separation, and the masses of the deflected ions are computed to identify ion species, wherein:
a burner for generating the plasma, a deflecting portion comprising electrodes for deflecting the ions, and an analyzer for separating the deflected ions according to mass, these being disposed in a plane in the horizontal direction, and a sample setting portion for setting the sample, a peristaltic pump for aspirating the sample and the burner which introduces and burns the aspirated sample are disposed in a plane in the vertical direction relative to the aforesaid plane. The sample is supplied to the burner from below, and the ions generated by the plasma are made to flow in a horizontal plane.
This invention further provides a plasma ion source mass spectrometer wherein a sample is converted to ions in a plasma, the ions are deflected to give a mass separation, and the masses of the detected ions are computed to identify ion species, wherein:
a burner box comprising a torch and nebulizer, a deflector and analyzer box comprising deflecting electrodes for deflecting ions and an analyzer for separating the deflected ions according to mass, a disk-shaped interface portion comprising an aperture in its center disposed between the burner box and deflecting electrodes, and a slide valve box, these elements being disposed in a plane in the horizontal direction, and in a basis housing these containers, the burner box slides in and out of the interface portion, an opened part is formed for controlling the burner box, and a door is opened in this opened part.
This invention further provides a plasma ion source mass spectrometer wherein a sample is converted to ions in a plasma, the ions are deflected to give a mass separation, and the masses of the detected ions are computed to identify ion species, wherein:
a basis is formed of two layers, and
a container forming a burner comprising a torch and nebulizer, a container forming an analyzer room comprising deflecting electrodes for deflecting ions and a deflected ion mass separating portion, and a container comprising a slide valve disposed between the burner and the deflecting electrodes, are disposed in a horizontal direction in the upper layer, and
a sample supply source, and a peristaltic pump for aspirating the sample and supplying it to the nebulizer of the burner, are disposed underneath the burner in the lower layer, the sample being introduced to the basis from the lower layer.
This invention further provides a plasma ion source mass spectrometer wherein a sample is converted to ions in a plasma, the ions are deflected to give a mass separation, and the masses of the deflected ions are computed to identify ion species, wherein:
a basis is formed of two layers, wherein
a container forming a burner comprising a torch and nebulizer is disposed in the upper layer,
a peristaltic pump for aspirating the sample and supplying it to the nebulizer of the burner is disposed in the lower layer,
and in the upper layer of the basis, an opened part is formed in the container forming the burner to check the combustion state, doors are provided to seal the opened part, and a check window is formed in these doors.
This invention further provides a plasma ion source mass spectrometer wherein the doors comprise a door in which the check window is formed, and a maintenance door.
This invention further provides a plasma ion source mass spectrometer wherein part of the peristaltic pump is disposed inside the basis, part is disposed outside the basis, and the pump is provided in a pump opening formed in the basis.
This invention further provides a plasma ion source mass spectrometer wherein a matching box is disposed underneath and at the side of the burner box.
This invention further provides a plasma ion source mass spectrometer wherein a container comprising electrodes for deflecting ions and an analyzer room comprising a deflected ion mass separating portion, and a container comprising a slide valve disposed between a burner and the deflecting electrodes, are disposed in the horizontal direction of a container forming the burner, and are supported by a matching box.
This invention further provides a plasma ion source mass spectrometer wherein the burner is disposed on a control side, the analyzer room is disposed to the rear, and the burner and peristaltic pump are disposed in proximity to each other.
This invention further provides a plasma ion source mass spectrometer wherein the container forming the burner is open on its control side and upper side, and a chimney is formed in the basis.
This invention further provides a plasma ion source mass spectrometer comprising a plasma ion source for converting a sample to ions in a plasma, and a mass analyzer for analyzing the sample ions generated by the plasma ion source, wherein:
an introducing path for a sample which has passed via a setting portion for setting the sample, a burner for generating the plasma, an interface portion for introducing ions into a vacuum portion, an ion optics for enhancing ion transmission efficiency in the vacuum portion, and deflecting electrodes for deflecting ions to reach the mass analyzer, has two bends.
This invention further provides a plasma ion source mass spectrometer comprising a plasma ion source for converting a sample to ions in a plasma, and a mass analyzer for analyzing sample ions generated by the plasma ion source, further comprising:
a sample setting portion for setting the sample, a burner for generating the plasma, an interface portion for introducing ions into the vacuum portion, an ion optics for enhancing ion transmission efficiency in the vacuum portion, and deflecting electrodes for deflecting the ions, wherein the sample setting portion and burner are arranged in the height direction, the burner, interface portion, ion optics and deflecting electrodes are arranged in a horizontal direction, and the deflecting electrodes and mass analyzer are arranged in a vertical direction.
This invention further provides a plasma ion source mass spectrometer comprising a plasma ion source for converting a sample to ions in a plasma, and a mass analyzer for analyzing sample ions generated by the plasma ion source, comprising:
a sample setting portion for setting the sample, a burner for generating the plasma, the interface portion for introducing ions into the vacuum portion, an ion optics for enhancing ion transmission efficiency in the vacuum portion, and deflecting electrodes for deflecting the ions, wherein the sample setting portion and burner are arranged in the height direction, the burner, interface portion, ion optics and deflecting electrodes are arranged in a horizontal direction, and the deflecting electrodes and mass analyzer are arranged in the height direction.
This invention further provides a plasma ion source mass spectrometer comprising a plasma ion source for converting a sample to ions in a plasma, and a mass analyzer for analyzing sample ions generated by the plasma ion source, comprising:
a sample setting portion for setting the sample, a burner for generating the plasma, an interface portion for introducing ions into the vacuum portion, an ion optics for enhancing ion transmission efficiency in the vacuum portion, and deflecting electrodes for deflecting the ions, wherein the sample setting portion, burner, interface portion, ion optics and deflecting electrodes are arranged in the height direction.
This invention further provides a plasma ion source mass spectrometer comprising a plasma ion source for converting a sample to ions in a plasma, and a mass analyzer for analyzing sample ions generated by the plasma ion source, comprising:
a sample setting portion for setting the sample, a burner for generating the plasma, an interface portion for introducing ions into the vacuum portion, an ion optics for enhancing ion transmission efficiency in the vacuum portion, and deflecting electrodes for deflecting the ions, wherein
the sample setting portion and burner are arranged in a first direction,
the burner, interface portion, ion optics and deflecting electrodes are arranged in a second direction,
and the deflecting electrodes and mass analyzer are arranged in a third direction different from the aforesaid first and second directions.
This invention further provides a plasma ion source mass spectrometer comprising a plasma ion source for converting a sample to ions in a plasma, and a mass analyzer for analyzing sample ions generated by the plasma ion source, comprising:
a sample setting portion for setting the sample, a burner for generating the plasma, an interface portion for introducing ions into the vacuum portion, an ion optics for enhancing ion transmission efficiency in the vacuum portion, and deflecting electrodes for deflecting the ions, wherein
the sample setting portion and burner are arranged in a first direction, and
the burner, interface portion, ion optics and deflecting electrodes are arranged in a second direction, and
the deflecting electrodes and mass analyzer are arranged in the aforesaid first direction.
This invention further provides a plasma ion source mass spectrometer comprising a plasma ion source for converting a sample to ions in a plasma, and a mass analyzer for analyzing sample ions generated by the plasma ion source, comprising:
a sample setting portion for setting the sample, a burner for generating the plasma, an interface portion for introducing ions into the vacuum portion, an ion optics for enhancing ion transmission efficiency in the vacuum portion, and deflecting electrodes for deflecting the ions, wherein
the sample setting portion, burner, interface portion, ion optics and deflecting electrodes are arranged in a desired direction.